Chair armrest adjustment mechanism

Abstract

A chair armrest adjustment mechanism for an armrest is disclosed. The armrest adjustment mechanism includes a first member, an upstanding second member for mounting to an armrest support member, and a third member having attachment means for fixedly attaching the third member to an armrest pad. The third member and the second member have a pin and slot arrangement to limit the rotational movement of the third member. The first member is pivotally mounted to the second member via a pin such spring cups between the first member and the second member at either side of the pin for biasing the first member to a level orientation with respect to the second member.

We claim: 
     
       1. A chair armrest adjustment mechanism comprising: a top member having attachment means for mounting said member to an armrest pad,   support means for mounting to an armrest support,   mounting means for mounting said top member to said support means for side-to-side rotational movement of said top member relative to said support means,   limiting means for limiting side-to-side rotational movement of said top member on said support means comprising a pin and slot arrangement, said pin extending from one of said top member and said support means and said slot extending in another of said top member and said support means, said slot comprising an arcuate array of holes, each of said holes sized such that on insertion of said pin into any one of said holes, said top member is fixedly positioned with respect to side-to-side rotational movement on said support means.   
     
     
       2. The mechanism of claim 1 wherein said limiting means further comprises a further slot in said another of said top member and said support means, said further slot sized to provide free movement of said pin therein. 
     
     
       3. The mechanism of claim 2 wherein said mounting means comprise a boss extending from a first one of said top member and said support means and an opening in a second one of said top member and said support means for receiving said boss. 
     
     
       4. The mechanism of claim 3 wherein said slot of holes and said further slot are opposed to one another on either side of said boss. 
     
     
       5. The mechanism of claim 4 including means to bias said top member toward said support means such that said pin is biased toward a position within one of said slot of holes and said further slot. 
     
     
       6. The mechanism of claim 5 wherein said biasing means comprise a shaft extending from said boss through said second one of said top member and said support means, a clip supported on said shaft on a side of said second one which is opposite said first one, and a spring compressed between said clip and said second one. 
     
     
       7. The mechanism of claim 6 wherein said support means comprises an upstanding base member and a medial member, said upstanding base member for mounting to an armrest support, said top member being mounted to said medial member, said medial member being pivotally mounted by a pivot to said upstanding base member such that a front end of said top member may tilt upwardly and downwardly relative to said base member. 
     
     
       8. The mechanism of claim 7 including biasing means between said base member and said medial member for biasing said medial member to a level position, said biasing means comprises a spring positioned on either side of said pivot. 
     
     
       9. The mechanism of claim 8 wherein said top member and said medial member comprise a tongue and groove arrangement therebetween to limit rotational movement of said top member relative to said medial member. 
     
     
       10. The mechanism of claim 1 including a raised pad on a face of one of said top member and said support means, said face facing another of said top member and said support means, said pad for reducing the frictional resistance between said top member and said support means during side-to-side rotational movement of said top member. 
     
     
       11. A chair armrest adjustment mechanism comprising: a top member having attachment means for mounting said member to an armrest pad;   support means for mounting to an armrest support;   mounting means for mounting said top member to said support means for side-to-side rotational movement of said top member relative to said support means; and   one of said top member and said support means comprising a raised pad facing the other of said top member and said support means, for reducing the frictional resistance between said top member and said support means during rotational movement.   
     
     
       12. The mechanism of claim 11 including limiting means for limiting side-to-side rotational movement of said top member on said support means comprising a pin and slot arrangement, said pin extending from one of said top member and said support means and said slot extending in another of said top member and said support means, said slot comprising an arcuate array of holes, each of said holes sized such that on insertion of said pin into any one of said holes, said top member is fixedly positioned with respect to side-to-side rotational movement on said support means. 
     
     
       13. The mechanism of claim 12 wherein said limiting means further comprises a further slot in said another of said top member and said support means, said further slot sized to provide free movement of said pin therein. 
     
     
       14. The mechanism of claim 13 including means to bias said top member toward said support means such that said pin is biased toward a position within one of said slot of holes and said further slot. 
     
     
       15. The mechanism of claim 14 wherein said support means comprises an upstanding base member for mounting to an armrest support and a medial member to which said top member is mounted, said medial member pivotally mounted to said upstanding base member such that a front end of said top member may tilt upwardly and downwardly relative to said base member.